In [1]}, the issue of defining power in an ideal reverberant space was raised.
While the average local power is null across all angles of incidence (\(4\pi \)  sr), this does not preclude significant nonzero fluctuations of power that may still produce physical effects and require characterization.
Near a perfect electric conducting (PEC) boundary, the average power [2]} and energy [3]}–[4]} of random fields are both nonzero and exhibit different spatial dependencies, through decaying interference at-a-distance, unlike for deterministic fields.
One consequence is the recommendation to avoid using a boundary layer zone of quarter-wavelength thickness near any metallic surface inside a MSRC [5]}. However, this guard distance creates practical problems in testing heavy floor-standing equipment or inside small cabinets. More generally, it is wasteful of the available interior space, particularly at relatively low frequencies.
Some studies have started to address this issue [2]}, [7]}, [8]}, [9]}, with a view to increase the working volume of a MSRC up to its physical boundaries. To this end, the full statistical characterization of the EM energy and power in the boundary zone is required.
